A brief article in yesterday's New York Times notes that California, by having among the highest tobacco taxes around, and by spending significantly on tobacco education and counter-marketing, has the lowest adult smoking rate of any state except Utah, and has seen rats of lung cancer decrease at a rate three times as fast as the rest of the country. All told, the state calculates that it has saved $86 billion in health care costs. (I can't find the actual report, so I would discount this somewhat). There's more detail at this blog, and here's a link to a press release from September.